Help 351C 4V Drivers side head not getting oil when priming motor

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We pulled the motor and took the plugs out on rear of block right side filled with oil left side dry. Looks like a total tear down unless we can figure this out.
Sure sounds like the #5 bearing at this point.
 
I'm assuming you checked the right side plug depth? Run a wire down the passage from the plug down to the main bearing to check for obstruction. Otherwise you could pull the pan and check # 5 main bearing orientation. I'm really curious about what the issue is.
 
I'm assuming you checked the right side plug depth? Run a wire down the passage from the plug down to the main bearing to check for obstruction. Otherwise you could pull the pan and check # 5 main bearing orientation. I'm really curious about what the issue is.
Well egg on my face! eggonface2.jpgUpon further rumination I went back to some tech files to confirm my suggestions. Actually I was WRONG that the bearing orientation would cause your problem. Even if it was not orientated correctly it wouldn't impede oil flow to the left side oil gallery. As the picture of the #5 main saddle shows, the oil transfers from one side to the other UNDER the bearing shell. So if you do take off #5 main cap and bearing shell, along with the pipe plugs out, you can verify by sight if both passages are unrestricted.
 

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  • Oil galley transfer passage 351C.png
    Oil galley transfer passage 351C.png
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It takes a real man to admit they are wrong.
Plan on tearing it apart to identify the real cause. I will definitely let everyone know what we find.
Good luck and keep us posted. What's left now is that you probably have a plugged galley (or something going on with #5 cam bearing) somewhere between the oil pressure gauge port and #8 lifter.
 
I'm wondering if the left front galley plug was left out. I would think there would be a lot of oil flowing in that area if it was. You should be able to see the oil flowing by looking down into the distributor hole while spinning the pump (if that plug is missing). It's a fast/easy check to make if you haven't begun tearing down already.
 
We have oil. We pulled the motor last night. The only thing I did was remove both rear galley plugs and work a 1/16 wire into both oil galleys,IMG_6399.jpeg
View attachment IMG_6411.mov
all the way down to #5 bearing. I got some dirt out on the wire. Then tonight used a “T” handle to drive the pump and sure enough oil started pushing through on drivers side head. The crank seems a little tight so plan on taking it to machine shop and get their thoughts if I should tear it down.
 
If you had enough dirt to cause your problem you should take the engine apart down to the bare block. When you got oil flowing into the left side I guarantee you carried some dirt with it into the galley and cylinder head.
Do thorough cleaning of the block including all of the oil gallerys. Same goes for the cylinder heads. I learned the hard way many moons ago, the engine block and heads have to be scrupulously CLEAN. Done correctly it's a pain in the ass. Actually more like a pain in your fingers and hands. LOL However any dirt that remains will comeback to haunt you in one way or another. Good luck moving forward. Consider this a learning experience.
 
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Took the assembled engine to the machine shop this morning to get his input, he also felt the crank it was a little tight. But since he didn't build it said there are too many variables that he didn't know. Gave him the history and he said where did the blockage end up. He will be getting the bare block to clean, inspect and machine if needed to get everything correct. he asked for the crank, pistons and cam and lifters.
 
Yes it was in CCW. Believe me I was double checking all the obvious possibilities. I was even questioning the amount of oil in the motor. The machine shop will go over the block and make sure everything is correct.
 
We have oil. We pulled the motor last night. The only thing I did was remove both rear galley plugs and work a 1/16 wire into both oil galleys,

all the way down to #5 bearing. I got some dirt out on the wire. Then tonight used a “T” handle to drive the pump and sure enough oil started pushing through on drivers side head. The crank seems a little tight so plan on taking it to machine shop and get their thoughts if I should tear it down.
I am glad you figured this out and kept us posted.
 
I did find debris in the galley leading from the passenger side galley that feeds the main #5 bearing that was restricting flow to the drivers side lifter galley.
The motor is now at the machine shop and they are going to inspect everything and assemble the bottom end. I have full confidence it will be done correctly when I get it back. I am handy mechanically, but am a welder by trade. It is best to let this part up to the professionals.
Thanks for all your help, I now have a VERY good understanding of how the oiling system works on a 351C.
 

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